The invention relates generally to call processing in communication systems, and more particularly to systems in which calls or other communications are directed by a switch to or from wired or wireless telephones or other types of user terminals.
Conventional communication system switches, such as private branch exchanges (PBXs) and other premises-based telephone switches, generally support a wide variety of useful features, such as bridged call appearances, hunt groups, call forwarding, navigable directories, multi-call conferencing, etc. However, these and other switch-based features are typically provided only to those user terminals that represent internal extensions within the premises serviced by the switch. As a result, a user terminal associated with an external network is generally unable to avail itself of the full set of features supported by the switch.
By way of example, an incoming call originating from a mobile telephone or other mobile device and directed to an internal extension serviced by the switch typically appears to the called party terminal simply as an externally-originated call. The caller and called party therefore typically do not have available to them the full range of switch services for use in processing the call. Conventional switches are unable to extend the switch-based features to such a call in an efficient and cost-effective manner.
It is known in the art to process call initiation requests generated by computer-telephony integration (CTI) applications external to a PBX or other communication system switch. Such techniques are described in U.S. Pat. No. 6,038,302 issued Mar. 14, 2000 in the name of inventors Didina Burok, Brian Hillis and Steven Michael Silverstein and entitled xe2x80x9cMethods and Apparatus for Processing Phantom Calls Placed Via Computer-Telephony Integration (CTI),xe2x80x9d which is incorporated by reference herein. In these techniques, the originator is a xe2x80x9cphantomxe2x80x9d extension that does not correspond to a physical communication device of the system. However, these and other known techniques do not adequately address the above-noted problems associated with calls originating from mobile telephones or other external user terminals and directed to particular internal extensions serviced by the switch.
A need therefore exists for call processing techniques that allow external user terminals to access premises-based communication switch features in a manner similar to an internal extension serviced by the switch.
The present invention provides methods and apparatus for processing an incoming call received in a switch from an external network, in a manner that allows the corresponding originator terminal or other external endpoint to be treated as if it were an internal extension serviced by the switch.
In accordance with one aspect of the invention, an incoming call received in a private branch exchange (PBX) or other communication system switch from a mobile telephone or other originator terminal of the system is processed to determine an associated identifier. The originator terminal is utilizable external to a premises serviced by the switch, and does not have an extension associated with any internal endpoint serviced by the switch. The switch attempts to map the identifier associated with the incoming call to a corresponding entry in a stored list of external endpoints registered with the switch. If the identifier has a corresponding entry on the list, the switch processes the incoming call such that it appears to a destination terminal as being originated by an internal extension. For example, the incoming call may be processed as if it originated from a particular internal extension assigned to the corresponding originator terminal. More particularly, an internal alerting indicator and associated station display identifying an extension assigned to the originator terminal may be provided at the destination terminal.
In accordance with another aspect of the invention, a user at an originator terminal may be permitted to access one or more features of the switch after an identifier of an incoming call from that originator terminal to a remote access extension has been associated with a corresponding entry in the stored list of external endpoints. More particularly, after the incoming call to the remote access extension is connected, and the identifier of the incoming call is associated with an entry in the stored list, the user may access the one or more features of the switch by entering a designated security code followed by appropriate feature access codes.
Advantageously, the invention allows a mobile telephone or other external endpoint to be treated as if it were an actual internal extension serviced by the switch. This in turn allows a given external endpoint to access at least a subset of the desirable call processing features provided by the switch, and thereby overcomes one or more of the above-described problems associated with conventional techniques.